Automatic drain device



' 1927 A. L. MITCHELL AUTOMATIC DRAIN DEVICE Filed July 19. 1926 ATTORNEY.

Patented May 31, 1927.

UNITED STATES insan ARTHUR L. MITCHELL, OF DALLAS, TEXAS.

AUTOMATIC DRAIN DEVICE.

Application filed July 19,,

a drain outlet "for the water control valve of a water heater, whereby the coils of the water heater will be automatically drained when the water supply is cut oil.

A further object is to provide an escape valve in the valve disk arranged to be closed by the pressure of the water when the device in operation for supplying water to the coils and to automatically open to drain the coils when the supply of water is cut off.

A construction designed to carry out the invention'will be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, in which an example of the invention is shown and wherein:

Fig. 1 is a view of a water and gas valve assembly for a water heater Fig. 2 is a plan view of the water controlling valve with the cover removed and a portion in section,

Fig. 3 is a cross-sectional View taken on the line 33 01"" Fig. 2, and

Fig. 4 is an enlarged crosssectional view taken on the line 4--4 of Fig. 2.

In. the drawings the numeral 10 designates the usual gas controlling valve having a supply pipe 11 and distributing pipe 12 leading to the burners of the heater. The valve 10 has a stem 13 projecting from its top in the path of a stem 14: extending through the nipple 15 of the water valve casing 16. The lasing 16 has a central well 17 above the nipple and a cylindrical chamber 18 in the top of which a cap 19 is screwed.

A nipple 20 formed integral with the casing extendsirom one side and communicates with an upright duct 21 having a port 22 at its upper end entering the chamber. ()n the opposite side of the chamber a ver tical slot 23 forms the entrance to a bypass chamber 24 connected at its bottom to a duct 25 extending from the chamber to the well 17. A channel 26 leads from the well 17 to a nipple 27 extending from the side of the casing and screw-threaded for connection with the water coils (not shown) of the heater.

1926. Serial No. 123,502.

29 engaging withthe walls of the chamber to provide a water-tight connection. The

valve has a boss 30 extending upwardly from its center and this boss engages a stud 31 which depends from the cap 19 to limit the upward movement of the disk. The extrcmcnpper portion of the disk is just under the port 2 and partially above the upper end of the slot 23 so that water entering through the port can not escape through the slot until the va ve disk is depressed. The valve stem l l is connected at its upper end to a cylindrical shank 32 depending from the boss 80 and a coiled spring 33 surrounds the shank and stem between the boss and the well 17 I It will be seen that under ordinary conditions, the valve disk 28 is maintained in its upper position by the spring 33, but when water is admitted through the nipple 20, duct 21 and port 22 the pressure thereof will be sniiicient to depress the disk 18 so that thestem 14C will engage the stem 13 and open the gas valve and the water will flow around the disk through the slot 23, bypass chamber 24 and duct 25 to the lower part of the chamber 18, from which it will then pass out through the channel 26 and nipple 27 to the heater coils. The shank 32 will limit the downward movement of the valve.

The parts which have been described form the usual construction now in common use, and my invention is applied thereto.

In any suitable part of the disk 28 1 pro vide an aperture 34 and form the upperend oi? the same into a seat 35 for receivii'lg a ball valve 36. An angular ball retainerST having a ball aperture 38 is fastened to the disk by a screw 39. Theopening 38 immediately over the ball 36 and receives the latter when it is displaced upwardly, but prevents its displacement laterally from its seat. The disk 28 also has the usual bleed hole 40.

It will be seen that when the valve is being used, the pressure of the water entering through the port 22 will force the valve 36 to its seat so that no water will pass through the aperture 3%, butwhen the water supply pipe (not shown) is opened to drain the hot water pipes, the water from the coils of the heater will flow down to the nipple 27 and into the chamber 18. This backflowing water will pass up through the aperture 34, unseat the valve 36 and escape through the port 22, duct 21 and nipple 20 to the water automatically drain the heating coils and also it is believed will prevent bursting of the water valve 1i the same should freeze. It 1s obvious that under ordmary COIlCllflOlls,

nnlessthe valve was manually drained by the removal of a plug or other device, water would remain 1n the heating COIlS illlGl the latter would be damaged byfreezing. Various changes in the size and shape of the dillerentparts, as well as modifications and alterations, may be made within the scope of the appended claim.

What I claim, is;

A controlling valve for a water heater system comprising a disk having an aperture therethrough countersunk at its upper end =tofo1n1a 'a lverseat, a freely movable valve operable upon said seat to open said aperture only upon the relief of the inlet pressure to drain the system, and a retaining plate secured to the upper face of the disk and extended over said valve to limit its upward opening movement.

In testimony whereof l all-ix my signature.

ARTHUR L. hII'lClx I 

